these village elders tell me once u.s. troops leave, a civil war will begin and u.s.-trained afghan forces will not be able to stop it. >> are you preparing for this fight? are you already stockpiling weapons and ammunition and getting yourself ready? yes, we are, we will definitely fight, he says. and what about the afghan government? it's meaningless here, they say. you think it's possible that the taliban will try and come back. yes, they will, he says. it makes a decade's work of american battles seem futile. it wasn't always like this. >> the united states military has begun strikes. >> at first, the war had momentum. and a clear purpose. al qaeda with bases in afghanistan attack the united states on 9/11. just three months later, the u.s. drove the taliban from power, al qaeda and osama bin laden were on the run. it was done with a few hundred cia officers, special forces, and air power. a quick victory. but not decisive. >> that was nbc's richard engel reporting. and he goes on to report that they have made gains, mike barnicle, the life expectancy has extended